Governing mechanism for turbines.



L. GUBLIC GOVERNING MECHANISM POR TURBIEH'S.

11111111011110112111@ JULY so, 191sA lgg 16., .Patented Apr. 14, 1914.

i@ -Lmclvvi 'Cqbelio @my 5%@ sgg: Hslyfltt@ rrveg nnrr LUDWIG CUBELIC, OF CHARLTTENBRG, GEMIABTZ, ASSIGNGR T GENE ELECTRC COMPANY, A GORPGRATION 0F NEW YQRK.

GOVERNIN'G MECHANISM FOR TURBINES.

Specification of Letters Patent.

Application nieu July 3o, 1913. serial No. 781,989.

To ZZ Az/'wm it may concern.'

Be it known that I. LUouIIG CUBELIC, a subject of the King of Prussia, residing at Charlottenburg5- Germany, have invented certain new and useful Improvement-s in Governing Mechanisms for Turbines, of which the following is a specification.

The present invention relates to governing mechanisms for elastic fluid turbines and its object is to improve their construction by causing them to maintain more nearly uniform speed of the turbine from no load to full load. Such a result is especially desirable when the turbine is used to drive an electric generator whose periodicity of voltage varies with the speed. ln an ordinar v speed governor having eentrifugallv acting weights and a spring acting in opposition thereto the sleeve or other part moved by the joint action of the weights and springs has a considerable travel; in other words, the sleeve has a different position for different loads and speeds. This peculiarity of operation is ytroublesome when the turbine drives an `electric generator, and compels constant watchfulness on the part of the station attendants Ato correct for changes in periodicity or fluctuation in voltage arising therefrom. This correction 1s usually accomplished 'by the attendant making some supplementary regulation at the switchboard or changing thetension of the spring means at the governor which opposes the action of the weights. v

In a steam turbine, any variation in load is accompanied b v a corresponding change in the high pressure stage or stages and in the same sense. I utilize this fact in my improved mechanism and cause said -pressure changes to act automatically on the speed governor in' a manner to change the eifectve action of its main spring.

'In the accompanying drawing is shown a multi-stage turbine and governing mechanism illustrating one of the embodiments of my invention.

1 lindicates a multi-stage t-urbineot any desired character to which steam is admitted't'rom the main Q.. Between the main and turbine is a regulator such as a nozzle or throttle valve 3. A centrifugal speed governor 4 driven b v the turbine is provided for controlling the regulator. The reguvlatoris actuated by a steam or hydraulic motorlcomprising a cylinder 5 and piston lever 8. One end of the lever is connected to'an extension of the piston rod and forms a part of a follow-up device as is well understood, the other end being connected Patenten apr. ia, rara.

to the governor sleeve or collar 9. The pilot y valve is mounted in ay easing 10 and below it is a coiled compression spring 11 which rests on the upper end of a differential piston 12 located in the' cylinder 13. Under the piston is la compression spring 14 that tends at all times to raise it. The chamber under 'the piston is connected to atmosphere or it may be connected to vacuum if desired.

rlhe chamber above the enlarged piston is connected to a stage of the turbine, preferably the first because the changes in pressure are more pronounced therein than in the later stages buv the pipe 1G.l The spring 14 tends to raise the pilot valve 7 and through it act on the governor lever and the spring 15 of the governor. As the ldiiierential )iston changesits `position up or down it e ects a change in action of the speed governor by changing' the eti'ectve action nt the governor spring.

So long as the load on the turbine remains uniform, no variation of pressure occurs in its first stage. and the tension of the spring 14 is balanced by the steam acting upon the upper surface of the piston 1:2. Butif the .load on the turbine decreases, and the speed of the turbine increases, the governor balls rise, compressing the spring'l and lifting the valve 7 to admit Huid pressure above the piston 6 to close the throttle valve The decrease in load is', however, accompanied by a corresponding drop in the steam pressure in the first stage of the turbine. lThe tension Vof the spring 11 is therefore partially relieved by the lessening of the steam pressure on the piston 7, and said piston tends to rise and exert an upward pressure on the sleeve 9 of the governor through parts l1, i', S and 9 which largely counterbalance the increased downward thrust of the governor spring 15. When the load on the turbine increases, the eti'ect is the reverse, the spring 14 being compressed and relieving the tension on the spring 11 and hence decreasing the opposition to the governor spring 15.

In the ordinary type of governor the amount of compression of the spring 15 is speed change in the lower range of operation than in the high due to the arrangement o t thevfeights with respect to their fulcra and sprlng. In my improved construction. the

spring 1l acts/in opposition to the spring 15, and the amount of this opposition is dev termined by the load changes in response to the pressure in the first stage. This has the eect of modifying the action of the p-arts in that the governor will respond more quickly to a speed change and hence more quickly adjust the regulator or the new load condition. In other Words, the governor can be made to worlrover a smaller speed vrange from no load to full load than heretofore, and will more quickly respond to load changes. v

In accordance with the provisions of. the vpatent statutes, I have described the principles 'of gether 'Withthe apparatus vwhich I now consider to represent the best embodiment thereof; but I desire to the apparatus shown is only illustrative and 'that the invention vcan be carried out other means.

What I claim as new and desire to secure -l l. In combination, an elastic Huid turbine, a spring-loaded speed "governor, a regulator for the turbine controlled by the governor, and automatic means for varying the efective action vof the spring Qn the governor in response to varying loads onthe turbine.

an elastic-fluid turbine,

2. In combination,

overnorpa regulator a spring-loaded speed v for 'the turbine control ed by a spring 'acting on the governorin opposioperationV of my invention, t0.`

have it understood that turbine, of a throttle valve,

by Letters Patent of the United States, is:`

the governor,

tion to its spring, and a device 'responsive to load conditions on the turbine for hfanging the tension of the secondv mentioned sprlng.

3. The combinationvtvith. an elastic'iuid I turbine, of' a spring-loaded speed governor, and'means controlledV by the pressure in'a stage of the turbine for. opposing the tension of the spring.

4. 'Ihe combination. with anelastic iuid turbine, of -a spring-loaded'speed governor, v

ernor spring, and means responsive to varia-l tions in the pressure .in astage -of the turbine or controlling :the` action of said opposing spring.

5. The combination with an elastic fluid. turbine, of a sp-ring-loaded-speed-governor,

va spring opposingthe'tension, ofthe governor spring, a V'piston acting `upon the op-, posingspring, and means forsubjectin'g said iston to iiuid pressure from the first stage .of theturbine so that the action of: said op-fv posing -spring varies with variations in the4 stage lpressure'.

a spring opposingthe tension ,of'the gov- I.

6. The combination With an elastic iuid'- a motor for operating it comprising .a vpilot valve, a ring-loaded speed. governor, a lever therefor fulcrumed said pilot valve, a

differential piston acting4 against one endo said valve,` a spring 'abutting against the under side ofvsaidvpiston and .acting against the tension' of `the governor spring, and a pipe leading from a stageof theturbine to the upper side of said piston.

' In Witness whereof, I I my hand this 15 day of July, 1913.

l LUDWIG CUBELIC. Witnesses:

O'r'ro SoHMin'r, FRANZ Winnen.

have hereunto set 

